diff options
| author | Sage Weil <sage@newdream.net> | 2010-05-13 19:01:13 (GMT) |
|---|---|---|
| committer | Sage Weil <sage@newdream.net> | 2010-05-17 17:25:45 (GMT) |
| commit | b4556396fac5b3f063d5b8ac54dc02f7612a75e1 (patch) | |
| tree | 30f24bd81c4c007dd09fc625f202854803dd2628 | |
| parent | e1518c7c0a67a75727f7285780dbef0ca7121cc9 (diff) | |
| download | linux-b4556396fac5b3f063d5b8ac54dc02f7612a75e1.tar.xz | |
ceph: fix race between aborted requests and fill_trace
When we abort requests we need to prevent fill_trace et al from doing
anything that relies on locks held by the VFS caller. This fixes a race
between the reply handler and the abort code, ensuring that continue
holding the dir mutex until the reply handler completes.
Signed-off-by: Sage Weil <sage@newdream.net>
| -rw-r--r-- | fs/ceph/mds_client.c | 11 | ||||
| -rw-r--r-- | fs/ceph/mds_client.h | 2 |
2 files changed, 13 insertions, 0 deletions
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c index b3b19f0..c0568fe 100644 --- a/fs/ceph/mds_client.c +++ b/fs/ceph/mds_client.c @@ -1181,6 +1181,7 @@ ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode) if (!req) return ERR_PTR(-ENOMEM); + mutex_init(&req->r_fill_mutex); req->r_started = jiffies; req->r_resend_mds = -1; INIT_LIST_HEAD(&req->r_unsafe_dir_item); @@ -1715,8 +1716,16 @@ int ceph_mdsc_do_request(struct ceph_mds_client *mdsc, err = le32_to_cpu(req->r_reply_info.head->result); } else if (err < 0) { dout("aborted request %lld with %d\n", req->r_tid, err); + + /* + * ensure we aren't running concurrently with + * ceph_fill_trace or ceph_readdir_prepopulate, which + * rely on locks (dir mutex) held by our caller. + */ + mutex_lock(&req->r_fill_mutex); req->r_err = err; req->r_aborted = true; + mutex_unlock(&req->r_fill_mutex); if (req->r_locked_dir && (req->r_op & CEPH_MDS_OP_WRITE)) { @@ -1861,12 +1870,14 @@ static void handle_reply(struct ceph_mds_session *session, struct ceph_msg *msg) } /* insert trace into our cache */ + mutex_lock(&req->r_fill_mutex); err = ceph_fill_trace(mdsc->client->sb, req, req->r_session); if (err == 0) { if (result == 0 && rinfo->dir_nr) ceph_readdir_prepopulate(req, req->r_session); ceph_unreserve_caps(&req->r_caps_reservation); } + mutex_unlock(&req->r_fill_mutex); up_read(&mdsc->snap_rwsem); out_err: diff --git a/fs/ceph/mds_client.h b/fs/ceph/mds_client.h index 0b1dd10b..141a265 100644 --- a/fs/ceph/mds_client.h +++ b/fs/ceph/mds_client.h @@ -165,6 +165,8 @@ struct ceph_mds_request { struct inode *r_locked_dir; /* dir (if any) i_mutex locked by vfs */ struct inode *r_target_inode; /* resulting inode */ + struct mutex r_fill_mutex; + union ceph_mds_request_args r_args; int r_fmode; /* file mode, if expecting cap */ |